1. Field of the Invention
The present invention relates to a portable terminal such as a portable telephone or PDA, and, specifically, the present invention relates to a portable terminal apparatus that is formed by a plurality of housings that are joined such that one housing can be superimposed on the other housing, and in which a display screen of a display unit provided in one of the housings is visible to the outside in both a superimposed state and in non-superimposed states, and in which output information is displayed on the display screen in any of these states,
Priority is claimed to Japanese application No. 2002-287135, filed Sep. 30, 2002, which is incorporated herein by reference.
2. Description of Related Art
Conventionally, a folding portable telephone 2 such as that shown in FIG. 12 is generally known as a folding portable terminal apparatus having two foldable housings. This folding portable telephone 2 is provided with a speaker 13 and a display screen 12 such as a liquid crystal display (LCD) that displays output information on an inner surface 10 of one of the housings 4. A main input unit 16 and a microphone 15 are provided on an inner surface 14 of the other housing 6.
A cross key 18 that instructs movement in up and down directions as well as left and right directions, a ten key, and various other keys are provided on the main input unit 16 so that items to be displayed on the display screen 12 can be selected.
In this type of folding portable telephone 2, the respective functions performed by the folding portable telephone 2 are displayed on the display screen 12 as a selection screen. At this time, characters are displayed so that a user can understand what each function is, and these characters are arranged in a manner such as that shown in FIG. 8.
However, in the folding portable telephone 2 shown in FIG. 12, the drawback has existed that when the one housing 4 and the other housing 6 are folded shut the display screen 12 cannot be viewed unless the two housings are opened, and even if information is output to the display screen 12, this cannot be viewed with the housings in a folded shut state. In order to solve this type of annoying, time consuming drawback, portable telephones have been developed in which the display screen 12 faces outwards even when the portable telephone is in a folded state or in a state equivalent to a folded state.
An example of such a portable terminal apparatus is the superimposed type of portable terminal apparatus disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2002-141984. This superimposed type of portable terminal apparatus is formed such that, when the two joined housings are in an open state, a display surface provided in one of the housings faces inwards with the same attitude as the folding portable telephone 2 shown in FIG. 12.
However, unlike the folding portable telephone apparatus 2, this type of conventional superimposed portable terminal apparatus is structured such that one housing can be folded and superimposed on top of the other housing while being twisted 180 degrees around a joint portion where the two housings are joined. Therefore, the two housings can be superimposed with the display surface facing outwards.
However, even though a user is able to view the display surface, when the two housings are in a superimposed state, the main input unit is covered up and hidden by the display surface housing. Therefore, it is not possible to operate the input unit. In order to solve this type of problem, as in the invention disclosed in JP-A No. 2002-33809, an auxiliary input key is provided on the surface on the side of the housing.
Because there is a limit on the surface area and width of the surface on the side of the housing, it is difficult to use a cross key or a key equivalent to a cross key as the auxiliary input key. Therefore, even if it is possible when the two housings are in a superimposed state to view the various functions provided in the portable telephone 2 via the display unit, as is shown in FIG. 8, items displayed as characters can only be displayed arranged one-dimensionally in a vertical direction on a selection screen. Moreover, the same selection screen is displayed on the display surface regardless of whether the housings are in a superimposed state or in an open state.
However, when a selection screen on which items displayed as characters are arranged one dimensionally is displayed on a display surface whose size is limited, as is the case with the portable telephone 2, if a user wishes to display a large number of items at the same time the characters shrink in size and become difficult to read. In contrast, if the characters are enlarged, the number of items that can be displayed at the same time is decreased. Therefore, when searching for a particular item it is necessary to scroll through the selection screen by operating the auxiliary input key, which is a drawback from the standpoint of operability.
Moreover, in a conventional superimposed type of portable terminal apparatus, because the aforementioned selection screen is displayed regardless of whether the housings are in a superimposed state or an open state, although it is possible to select up, down, left, and right using a cross key or the like of the main input unit in the open state. However, when selecting an item on the selection screen, because only operations in the up and down direction can be used, the drawback has existed that the functions of the main input unit cannot be satisfactorily put to use.
Therefore, it is an aim of the present invention to provide a superimposed type of portable terminal apparatus that has one selection screen for when the two housings are superimposed and another selection screen for when they are open. That is, in cases when the two housings are superimposed and the main input unit cannot be operated, the superimposed type of portable terminal apparatus displays on the display unit a selection screen that allows input to be made using an auxiliary input unit, while in cases when the two housings are opened and the main input unit can be operated, the superimposed type of portable terminal apparatus displays on the display unit a selection screen that is easy to read and that allows full use to be made of the functions of the main input unit.